Disposable self-shielding unit dose syringe guard

Abstract

The present invention is directed to an improved guard for a medical cartridge, such as a unit dose syringe or ampule, comprising a body for receiving the cartridge, and a shield slidably attached to the body. In one form, the guard includes only two parts which are preassembled and ready to receive a cartridge having its own plunger. The body has locking detents which permanently hold the cartridge in the guard, and has cooperating detents and detent pockets which allow the shield to be directed distally, from an unguarded position in which the needle on the cartridge is uncovered for delivery of medication, to a guarded position in which the needle is permanently covered for disposal. In a second form, the guard also includes a plunger assembly for a cartridge not having its own plunger. The plunger assembly is locked onto the body, permanently holding the cartridge received therein. The parts of the device are preferably molded from plastic and may be clear or of a color, such as a latex color or skin tone.

What is claimed is:  
     
       1. A self-shielding guard for a medical cartridge having a proximal end and a distal end, and having its own needle extending from the distal end, said guard comprising: 
       a body having a cavity adapted to receive the cartridge axially therein through an open proximal end of said body, and having a distal end including an opening through which the needle may extend when the cartridge is received within said cavity;  
       locking detents on said proximal end of said body for substantially permanently engaging the proximal end of the cartridge received in said cavity;  
       a shield slidably attached to said body, and having open proximal and distal ends, said shield being slidable between an unguarded and a guarded position, thereby uncovering and covering respectively the needle on the cartridge; and  
       cooperating detents and detent pockets formed in said body and said shield for mutually engaging to hold said shield in said guarded position;  
       wherein said cooperating detents and detent pockets comprise:  
       a first set and a second set of detent pockets formed in said body, said second set being located distally from said first set; and  
       a plurality of detents on said shield adapted to engage said detent pockets, said unguarded position being defined by said detents engaging said first set of detent pockets, and said guarded position being defined by said detents engaging said second set of detent pockets.  
     
     
       2. The self-shielding guard of claim  1  wherein said detents are integrally molded to said shield adjacent said proximal end. 
     
     
       3. The self-shielding guard of claim  1  wherein said detents have sloping distal edges and blunt proximal edges, and wherein said first set of detent pockets have sloping distal edges, whereby said shield may be moved from said unguarded position by slidably disengaging said detents from said first set of detent pockets along said sloping distal edges. 
     
     
       4. The self-shielding guard of claim  1  wherein said second set of detent pockets have blunt proximal edges and said detents have blunt proximal edges, whereby when said shield is directed to said guarded position, said blunt proximal edges of said detents engage said blunt proximal edges of said second set of detent pockets, preventing said shield from being proximally moved from said guarded position. 
     
     
       5. The self-shielding guard of claim  1  wherein said body further comprises a finger grip integrally molded to said proximal end of said body, and wherein said first set of detent pockets are located adjacent said finger grip. 
     
     
       6. A self-shielding guard for a medical cartridge having a proximal end and a distal end, and having its own needle extending from the distal end, said guard comprising: 
       a body having a cavity adapted to receive the cartridge axially therein through an open proximal end of said body, and having a distal end including an opening through which the needle may extend when the cartridge is received within said cavity;  
       locking detents on said proximal end of said body for substantially permanently engaging the proximal end of the cartridge received in said cavity;  
       a shield slidably attached to said body, and having open proximal and distal ends, said shield being slidable between an unguarded and a guarded position, thereby uncovering and covering respectively the needle on the cartridge; and  
       cooperating detents and detent pockets formed in said body and said shield for mutually engaging to hold said shield in said guarded position;  
       wherein said body further comprises a finger grip section attached to said proximal end of said body, said finger grip section including said locking detents thereon;  
       wherein said finger grip section comprises a plunger slidably attached to said finger grip section, said plunger having a distal end attachable to a piston in the cartridge, thereby allowing said plunger to slidably direct the piston distally and proximally.  
     
     
       7. A self-shielding guard for a medical cartridge having a proximal end and a distal end, and having its own needle extending from the distal end, said guard comprising: 
       a body having a cavity adapted to receive the cartridge axially therein through an open proximal end of said body, and having a distal end including an opening through which the needle may extend when the cartridge is received within said cavity;  
       locking detents on said proximal end of said body for substantially permanently engaging the proximal end of the cartridge received in said cavity;  
       a shield slidably attached to said body, and having open proximal and distal ends, said shield being slidable between an unguarded and a guarded position, thereby uncovering and covering respectively the needle on the cartridge; and  
       cooperating detents and detent pockets formed in said body and said shield for mutually engaging to hold said shield in said guarded position;  
       wherein said body further comprises a finger grip section attached to said proximal end of said body, said finger grip section including said locking detents thereon;  
       wherein said finger grip section includes a plurality of locking fingers, and said proximal end of said body includes tapered pockets adapted to receive said locking fingers, said finger grip section being lockably attached to said body when said locking fingers fully engage said tapered pockets.